package oopday03;

public class UploadDemo {
    public static void main(String[] args) {
        Eoo o1 = new Eoo();
        o1.a = 1;
        o1.show();

        Foo o2 = new Foo();
        o2.b = 2;
        o2.test();
        o2.a = 2;
        o2.show();

        Eoo o3 = new Foo();//向上造型
        o3.a=1;
        o3.show();
       //o3.b= 2;//编译错误，能点出来什么，看引用类型
    }
}
